Effects of Pasturella Multocida B:2 and its immunogens (LPS and OMP) on reproductive hormones in Nili-Ravi Buffaloes

Abstract Livestock is a fundamental part of the agriculture industry in Pakistan and contributes more than 11.53% to GDP. Among livestock species, the buffaloes are regarded as the black gold of Pakistan. Being the highest milk producers globally, Nili-Ravi buffaloes are the most famous ones. Buffaloes are affected by many endemic diseases, and "Hemorrhagic septicemia" (HS) is one of them. This study was designed to ascertain the effects of experimental exposure ofP. multocida B:2 (oral) and its immunogens, i.e., LPS (oral and intravenous) and OMP (oral and subcutaneous) on reproductive hormonal profiles in Nili-Ravi buffaloes. Repeated serum samples were collected from the jugular vein of experimental animals for 21 days (0, 02, 04, 08, 12, 16, 20, 24, 36, 48, 72, 120, 168, 216, 264, 360, 456 and 504 hours). Hormonal assays to determine the serum concentrations of Gonadotropin-releasing hormone (GnRH), Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Estrogen (E2) and progesterone (P4) were performed using (MyBioSource) commercial Elisa kits. The hormonal profile of all treatment groups of the buffalo heifers exhibited significant (P 0.05) variations as compared to the control group (G-1). These results indicate suppression in Nili-Ravi buffaloes' reproductive hormonal profile on exposure to P. multocida B:2 and its immunogens. This influence warrants that exposure to H.S may be a possible reason for delayed puberty and poor reproduction performance in Nili-Ravi buffaloes.

Resumo A pecuária é uma parte fundamental da indústria agrícola no Paquistão e contribui com 11,53% do PIB nacional. Entre as espécies de gado, os búfalos são considerados o ouro negro do Paquistão. Sendo os maiores produtores de leite em todo o mundo, os búfalos Nili-Ravi são os mais famosos. Os búfalos são afetados por muitas doenças endêmicas, entre as quais a septicemia hemorrágica (SH). Este estudo busca verificar os efeitos da exposição experimental de P. multocida B:2 (oral) e seus imunógenos, ou seja, LPS (oral e intravenoso) e OMP (oral e subcutâneo), nos perfis hormonais reprodutivos em búfalos Nili-Ravi. Amostras de soro repetidas foram coletadas da veia jugular de animais experimentais por 21 dias (0, 2, 4, 8, 12, 16, 20, 24, 36, 48, 72, 120, 168, 216, 264, 360, 456 e 504 horas). Os ensaios hormonais para determinar as concentrações séricas do hormônio liberador de gonadotrofina (GnRH), hormônio foliculoestimulante (FSH), hormônio luteinizante (LH), estrogênio (E2) e progesterona (P4) foram realizados usando kits comerciais Elisa (MyBioSource). O perfil hormonal de todos os grupos de tratamento das novilhas bubalinas apresentou variações significativas (P 0,05) em relação ao grupo controle (G-1). Esses resultados indicam supressão no perfil hormonal reprodutivo de búfalos Nili-Ravi na exposição a P. multocida B:2 e seus imunógenos. Essa influência garante que a exposição à SH possa ser uma possível razão para o atraso da puberdade e o baixo desempenho reprodutivo em búfalos Nili-Ravi.

Effects of Pasturella Multocida B: 2 and its immunogens (LPS and OMP) on reproductive hormones in Nili-Ravi Buffaloes / Efeitos de Pasteurella multocida B: 2 e seus imunógenos (LPS e OMP) em hormônios reprodutivos em búfalos Nili-Ravi

Abstract Livestock is a fundamental part of the agriculture industry in Pakistan and contributes more than 11.53% to GDP. Among livestock species, the buffaloes are regarded as the black gold of Pakistan. Being the highest milk producers globally, Nili-Ravi buffaloes are the most famous ones. Buffaloes are affected by many endemic diseases, and "Hemorrhagic septicemia" (HS) is one of them. This study was designed to ascertain the effects of experimental exposure ofP. multocida B:2 (oral) and its immunogens, i.e., LPS (oral and intravenous) and OMP (oral and subcutaneous) on reproductive hormonal profiles in Nili-Ravi buffaloes. Repeated serum samples were collected from the jugular vein of experimental animals for 21 days (0, 02, 04, 08, 12, 16, 20, 24, 36, 48, 72, 120, 168, 216, 264, 360, 456 and 504 hours). Hormonal assays to determine the serum concentrations of Gonadotropin-releasing hormone (GnRH), Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Estrogen (E2) and progesterone (P4) were performed using (MyBioSource) commercial Elisa kits. The hormonal profile of all treatment groups of the buffalo heifers exhibited significant (P<0.05) variations as compared to the control group (G-1). These results indicate suppression in Nili-Ravi buffaloes' reproductive hormonal profile on exposure to P. multocida B:2 and its immunogens. This influence warrants that exposure to H.S may be a possible reason for delayed puberty and poor reproduction performance in Nili-Ravi buffaloes.

Resumo A pecuária é uma parte fundamental da indústria agrícola no Paquistão e contribui com 11,53% do PIB nacional. Entre as espécies de gado, os búfalos são considerados o ouro negro do Paquistão. Sendo os maiores produtores de leite em todo o mundo, os búfalos Nili-Ravi são os mais famosos. Os búfalos são afetados por muitas doenças endêmicas, entre as quais a "septicemia hemorrágica" (SH). Este estudo busca verificar os efeitos da exposição experimental de P. multocida B:2 (oral) e seus imunógenos, ou seja, LPS (oral e intravenoso) e OMP (oral e subcutâneo), nos perfis hormonais reprodutivos em búfalos Nili-Ravi. Amostras de soro repetidas foram coletadas da veia jugular de animais experimentais por 21 dias (0, 2, 4, 8, 12, 16, 20, 24, 36, 48, 72, 120, 168, 216, 264, 360, 456 e 504 horas). Os ensaios hormonais para determinar as concentrações séricas do hormônio liberador de gonadotrofina (GnRH), hormônio foliculoestimulante (FSH), hormônio luteinizante (LH), estrogênio (E2) e progesterona (P4) foram realizados usando kits comerciais Elisa (MyBioSource). O perfil hormonal de todos os grupos de tratamento das novilhas bubalinas apresentou variações significativas (P < 0,05) em relação ao grupo controle (G-1). Esses resultados indicam supressão no perfil hormonal reprodutivo de búfalos Nili-Ravi na exposição a P. multocida B:2 e seus imunógenos. Essa influência garante que a exposição à SH possa ser uma possível razão para o atraso da puberdade e o baixo desempenho reprodutivo em búfalos Nili-Ravi.

Gene de virulência oipA de Helicobacter pylori como marcador molecular de gastropatias severas / Helicobacter pylori oipa virulence gene as a molecular marker of severe gastropathies

ABSTRACT Background: Helicobacter pylori is an etiologic agent of gastroduodenal diseases. The microorganism, considered a type I carcinogen, affects about 50% of the global population. H. pylori virulence factors are determinant for the clinical outcome of the infection. The outer inflammatory protein A (oipA) gene encodes an outer membrane adhesin and is related to severe gastropathies, such as gastric cancer. Objective: The aim of this study was to evaluate the association of the oipA gene with the severity of gastroduodenal diseases in dyspeptic patients in region Central Brazil. Methods: The polymerase chain reaction (PCR) was used to determine the presence of H. pylori. Samples positives were used for molecular screening of the oipA gene. Gastropathies were categorized as non-severe and severe diseases. Results: Approximately 68% of patients had H. pylori and 36% were infected with H. pylori oipA+ strains. Infection was significantly associated in patients aged over 44 years (P=0.004). However, there was no association between oipA and patients' age (P=0.89). Approximately 46% of patients infected with oipA+ strains had some severe illness. Gastric adenocarcinoma was the most frequent severe gastropathy. The H. pylori oipA genotype was inversely associated with the severity of gastroduodenal diseases (OR=0.247, 95%CI: 0.0804-0.7149 and P=0.007). Conclusion: The characterization of possible molecular markers will contribute to personalized medicine, impacting the prognosis of patients.

RESUMO Contexto: Helicobacter pylori é um agente etiológico de doenças gastroduodenais. O microrganismo, considerado cancerígeno tipo I, afeta cerca de 50% da população mundial. Os fatores de virulência do H. pylori são determinantes para o desfecho clínico da infecção. O gene da proteína inflamatória externa A (oipA) codifica uma adesina da membrana externa e está relacionado a gastropatias severas, como o câncer gástrico. Objetivo: O objetivo deste estudo foi avaliar a associação do gene oipA com a gravidade das doenças gastroduodenais em pacientes dispépticos na região Brasil Central. Métodos: A reação em cadeia da polimerase (PCR) foi utilizada para determinar a presença de H. pylori. Amostras positivas foram utilizadas para triagem molecular do gene oipA. As gastropatias foram categorizadas como doenças não severas e severas. Resultados: Aproximadamente 68% dos pacientes apresentaram H. pylori e 36% estavam infectados com cepas H. pylori oipA+. A infecção foi significativamente associada em pacientes com idade superior a 44 anos (P=0,004). No entanto, não houve associação entre oipA e a idade dos pacientes (P=0,89). Aproximadamente 46% dos pacientes infectados com cepas oipA+ tiveram alguma doença severa. O adenocarcinoma gástrico foi a gastropatia severa mais frequente. O genótipo oipA de H. pylori foi inversamente associado à gravidade das doenças gastroduodenais (OR=0,247, IC95%: 0,0804-0,7149 P=0,007). Conclusão: A caracterização de possíveis marcadores moleculares contribuirá para a medicina personalizada, impactando no prognóstico dos pacientes.

Usefulness of the outer membrane proteins of Shigella sonnei in developing an antibody-based immunoassay for the diagnosis of shigellosis

@#Conventional culture method and biochemical tests remain as the ‘gold standard’ method for the identification of S. sonnei which are time-consuming. We have discovered previously the potential of three OMPs of S. sonnei (33.3 kDa, 43.8 kDa and 100.3 kDa) as biomarkers in the diagnostic test for shigellosis. Here, we evaluated the performance of the outer membrane proteins of S. sonnei for the development of an antibody-based immunoassay for the detection of S. sonnei infections. All threetarget proteins were specifically recognized when probed with S. sonnei sera. In addition, another two potential proteins of molecular weight 29.0 kDa and 88.2 kDa in size were also exclusively recognized by the IgA when probed with S. sonnei sera. The optimized ELISA demonstrated higher sensitivity and specificity which exceeded 86.0%. In conclusion, the identified target proteins showed great potential as diagnostic biomarkers for the detection of S. sonnei infections in patients.

Detection of virulence genes and investigation of the immunogenicity of outer membrane proteins of Salmonella enterica

Salmonella enterica is one of the most important food-borne pathogens, causing a variety of diseases in humansand animals. This study aimed to detect the virulence genes in 33 S. enterica strains isolated from patients andto investigate the immunogenicity of the outer membrane proteins (OMPs) of S. enterica serovar Typhimurium.The aggregative fimbriae (agfA) gene was detected in all S. enterica isolates except one strain, SalmonellaParatyphi C strain SA7. In addition, 81.8% of the isolates harbored the sefC gene (fimbrial protein). However,all of the tested S. enterica isolates possessed the fimA, hilA, invA, stn, and misL virulence genes, regardless ofserovar. The predominant OMPs of S. enterica Typhimurium SA3 identified by 12% sodium dodecyl sulfatePolyacrylamide Gel Electrophoresis (PAGE) were used as eliciting antigens in the experimental mice. Theresults of the protection studies indicated that the selected OMPs conferred varying degrees of protection.However, the highest protection was observed using the 38-kDa OMP, which provided 100% protection tomice challenged with 50× LD50 of Salmonella Typhimurium SA3 and 75% protection to mice subjected toan even higher bacterial challenge of 100× LD50. The humoral response in mice caused by the 38-kDa OMPwas confirmed using an immunodiffusion assay. This 38-kDa OMP is a promising candidate for the vaccinedevelopment against S. enterica Typhimurium. Further research on the protein structure was recommended.

Una vacuna de vesículas de membrana externa de Vibrio cholerae es aún una promesa: Caracterización proteómica / Outer membrane vesicle vaccine from Vibrio cholerae is still a promise: Proteomic characterization

Las epidemias de cólera afectan a un gran número de países africanos, asiáticos y del Caribe. Los cambios climatológicos y las constantes migraciones hacen que esta enfermedad se extienda, por lo que resulta necesario disponer de vacunas protectoras. En el presente trabajo se caracterizó una nueva vacuna de vesículas de membrana externa (VMEs) obtenidas de Vibrio cholerae O1 biotipo El Tor serotipo Ogawa cepa C7258, en el Instituto Finlay de vacunas (Cuba), a través de métodos proteómicos. Se identificaron 53 proteínas presentes en las VME (4 proteínas por banda electroforética) separadas por electroforesis unidimensional (1D) y digeridas con tripsina. Los fragmentos obtenidos fueron separados por cromatografía líquida de alta resolución (HPLC) acoplada a espectrometría de masa, secuenciados e identificados mediante bases de datos de proteínas Swiss-Prot y TrEMBL. El patrón proteico obtenido presentó algunas de las proteínas (12 proteínas citoplasmáticas y 5 proteínas de membrana externa) sugeridas dentro del proteoma de buena calidad para candidatos vacunales. Se estudiaron las mejores condiciones para la separación de las proteínas a través de electroforesis bidimensional. Las VME evaluadas cuentan con una composición fundamentada en proteínas necesarias para garantizar una respuesta inmune que proteja contra Vibrio cholerae O1 biotipo El Tor serotipo Ogawa.

Cholera epidemics affect a large number of African, Asian and Caribbean countries. The climate changes and the constant migrations cause this disease to spread, making it is necessary to obtain protective vaccines. In the present work, a new vaccine of outer membrane vesicles (OMV) from V. cholerae O1 El Tor biotype Ogawa serotype strain C7258 at Finlay Institute of vaccines (Cuba) was characterized by proteomic methods. A total of 53 proteins present in the OMV (approximate ratio of 4 proteins by electrophoresis band) were identified, separated by one dimension electrophoresis and digested by tripsin method. The fragments were separated by high performance liquid chromatography (HPLC) coupled to mass spectrometry, sequenced and identified, using Swiss-Prot and TrEMBL protein databases. The pattern showed some proteins (12 cytoplasmic proteins and 5 outer membrane proteins) suggested within the highest quality proteome for vaccine candidate. The best conditions for proteins separation by two dimension electrophoresis were studied. The OMV composition was based on proteins described to the immunity response and protection against V. cholerae O1 El Tor biotype Ogawa serotype.

As epidemias de cólera afetam um grande número de países africanos, asiáticos e caribenhos. As mudanças climáticas e as constantes migrações fazem com que esta doença se espalhe, portanto é necessário ter vacinas protectoras. No presente trabalho, uma nova vacina de vesículas de membrana externa (VMEs) obtidas de Vibrio cholerae 01 biotipo El Tor sorotipo Ogawa cepa C7258, no Instituto de Vacinas Finlay (Cuba), através de métodos proteômicos. Foram identificadas 53 proteínas presentes nas VME (4 proteínas por banda eletroforética) separadas por eletroforese unidimensional (1D) e digeridas com tripsina. Os fragmentos obtidos foram separados por cromatografia de alta resolução (HPLC) acoplada a espectrometria de massa, sequenciados e identificados usando bancos de dados de proteínas Swiss-Prot e TrEMBL. O padrão proteico obtido apresentou algumas das proteínas (12 proteínas citoplasmáticas e 5 proteínas de membrana externa) sugeridas dentro do proteoma de boa qualidade para candidatos vacinais. As melhores condições para a separação de proteínas através de eletroforese bidimensional foram estudadas. As VME avaliados possuem uma composição baseada em proteínas necessárias para garantir uma resposta imune que proteja contra Vibrio cholerae O1 biotipo El Tor sorotipo Ogawa.

Caracterización proteómica de vesículas de membrana externa extraídas de Shigella sonnei / Proteomic characterisation of outer membrane vesicle extracted from Shigella sonnei

Las vacunas compuestas por vesículas de membrana externa (VMEs) previenen de manera exitosa la enfermedad meningocócica del serogrupo B. Esta plataforma tecnológica de obtención puede ser aplicada para otros patógenos bacterianos Gram negativos. Una vacuna de VMEs desarrollada contra Shigella sonnei fue obtenida a través de una extracción de componentes celulares y su caracterización por electroforesis en geles de poliacrilamida unidimensional (1D). Se estudiaron las mejores condiciones de solubilización de las muestras, separación electroforética e identificación a través de espectrometría de masas acoplada a cromatografía de alta presión después del corte de las bandas y su tratamiento enzimático con tripsina. En esta etapa se identificaron un total de 57 proteínas en 23 bandas (2,5 proteínas por banda escindida), 47 de las proteínas no repetidas. Las proteínas inmunogénicas presentes en VMEs de S. sonnei fueron cuantificadas en cuanto a masa molecular por 1D-Western blotting en membranas de nitrocelulosa con anticuerpos obtenidos a partir de ratones inmunizados con las VMEs. Como que las bandas electroforéticas 1D contenían más de una proteína, se estudiaron las mejores condiciones de separación por el método de electroforesis bidimensional (2D) para el establecimiento del mapa proteico; tal que el incremento del tamaño de las tiras, el tiempo de focalización y la aplicación catódica garantizaron la mayor resolución(AU)

Outer membrane vesicles (OMVs) vaccines successfully prevent Group B meningococcal disease. This platform technology may be applied against other Gram negative bacterial pathogens. An OMV vaccine against Shigella sonnei was prepared by detergent extraction of cells and characterised by one-dimensional polyacrylamide gel electrophoresis (1D). The protein components were quantified by staining and scanning and the composition of bands were defined by coupled high-performance low chromatography/electrospray ionization tandem mass spectrometry after band excision and in-gel trypsin digestion. 57 proteins contained in 23 bands (2.5 proteins/split band) were detected, 47 of them were not repeated. The S. sonnei OMVs immunogenic proteins were identified by 1D-immunoblotting, after transfer of proteins to a nitrocellulose membrane and treatment with antibodies generated by immunisation of mice with the OMVs. The bands detected by 1D had more than a single proteins, that is why we studied the best conditions for molecular separation by two-dimension electrophoresis (2D) for establishing the protein map; such that the increase of strips size, time of isoelectric focusing (IEF) and cup-cathodic loading guaranteed the highest resolution(AU)

Research progress of mechanisms outer membrane proteins of Helicobacter pylori and its adherence / 上海交通大学学报（医学版）

Helicobacter pylori is a predominant pathogen inducing long-term chronic infection of stomach. Its outer membrane proteins (OMPs) mainly include lipoprotein, fimbriae protein and some adhesions. The adhesions are closely related to the pathogenic processes of adherence, colonization, persistent infection and severe clinical outcomes. In addition, the fact that adherence is vital for colonization and pathogenicity has made it a focus to study the vaccines against adherence. The OMPs related to adherence, their receptors, mechanisms of adherence, and the vaccines are summarized in this review.

Toxicity of outer membrane vesicles derived from Acinetobacter baumannii strains with different drug-resistance spectrums / 中华临床感染病杂志

Objective To compare the toxicity of outer membrane vesicles ( OMVs) secreted by Acinetobacter baumannii strains with different drug-resistance spectrums.Methods Four Acinetobacter baumannii strains with different drug-resistance spectrums were collected (strain 33, 3237, B29 and 10), and OMVs produced by these strains were extracted and purified.BCA assay was used to determine the protein concentrations, and RAW264.7 cells were incubated with different concentrations of OMVs for 24 h. Cell viability was measured with CCK-8 assay, and gene expression of tumor necrosis factor-alpha ( TNF-α) , interleukin-6 ( IL-6) , interleukin-1 beta ( IL-1β) , keratinocyte-derived chemokine ( KC) and macrophage inflammatory protein 2 (MIP-2) was assessed by quantitative real-time PCR.One-way ANOVA was used for data analysis.Results According to the result of drug susceptibility test, strain 10 was extensively drug-resistant Acinetobacter baumannii ( XDRAB ) strain, strain B29 was multi-drug resistance Acinetobacter baumannii (MDRAB) strain, while strain 33 and 3237 were non-MDRAB strains.After incubated with different concentrations of OMVs for 24 h, cell viability of RAW264.7 declined with the increase of OMVs concentrations.OMVs released from strain10, B29 and 3237 significantly lowered the cell viability at the concentration of 5 μg/mL, while the cytotoxicity of OMVs released from strain 33 was much weaker, and no remarkable decrease in cell viability was observed even at the concentration of 25 μg/mL.OMVs of all strains induced the release of TNF-α, IL-6, IL-1β, KC and MIP-2 in RAW264.7 cells, and the levels of theses cytokines were increased with the concentration of OMVs.Inflammatory response in cells incubated with OMVs from strain 33 was the weakest, while OMVs from strain 10 induced strongest inflammatory response.KC and MIP-2 levels were significantly higher in RAW264.7 cells incubated with OMVs from strain 10 with a concentration of 5 μg/mL than that incubated with OMVs from other strains ( F=19.094 and 19.032,P<0.05 or <0.01).Conclusions OMVs from Acinetobacter baumannii strains with different drug-resistance spectrums are of different toxicity.OMVs from XDRAB and MDRAB strains have higher toxicities and may induce stronger inflammatory response.

Polymorphic membrane protein I of Chlamydia trachomatis：prokaryotic expression, purification, antibody preparation and identification / 中华皮肤科杂志

Objective To clone and express the polymorphic membrane protein I(PmpI)gene of Chlamydia trachomatis(Ct), and to assess the immunogenicity and biological characteristics of PmpI. Methods A bioinformatic software was used to analyze the sequence of the PmpI gene of Ct, and to predict B cell epitopes in PmpI. With Ct serovar D DNA as the template, PCR was performed to amplify the N?terminal region(from position 90 to 1464)of the PmpI gene, which was cloned into a prokaryotic expression vector pET28a to express the recombinant protein PmpI. A Ni?ion affinity chromatography column was used to purify the recombinant protein, which was used to immunize New Zealand rabbits for preparation of polyclonal antibodies. Western blot analysis was conducted to evaluate the immunogenicity of this protein. Results A comprehensive analysis was carried out on the secondary structure, flexible regions, hydrophilicity plot, antigenic index and surface probability plot of the protein, which suggested that PmpI had 8 dominant B?cell epitopes. The product of PCR targeting the PmpI gene of Ct serovar D showed a total length of 1 375 bp. The recombinant prokaryotic expression vector pET28a?PmpI was successfully constructed. A recombi?nant protein with a relative molecular mass of approximately 50 000 was successfully expressed after isopropylβ?d?1?thiogalactopyranoside (IPTG) induction, and purified by affinity chromatography. Polyclonal antibodies against the recombinant protein were successfully prepared. Conclusion The N?PmpI protein of Ct serovar D is cloned and expressed successfully, laying a foundation for further studies on its biological functions.

Reduced antibiotics sensitivity of Acinetobaoter baumannii induced by meropenem in vitro and related mechanism / 中华临床感染病杂志

Objective To investigate the mechanism related to reduced antibiotic sensitivity of Acinetobacter baumannii inducted by meropenem in vitro.Methods Three strains of clinically isolated carbapenems-sensitive Acinetobacter baumannii were induced by meropenem in vitro, and the mutant strains (MS1, MS2 and MS3) were obtained.Minimal inhibitory concentrations (MICs) of antimicrobial agents to strains before and after induction were determined by automatic drug sensitivity analyzer .The homology of strains was analyzed by Enterobacterial repetitive intergenic consensus -polymerase chain reaction ( ERIC-PCR).Modified Hodge test and EDTA-Na2-double disk synergy test were used to detect carbapenemase and metallo-β-lactamase (MBL), respectively.Main carbapenemase genes were detected by PCR and followed by DNA sequencing.Expressions of adeB and outer membrane proteins in strains before and after induction were detected with fluorescence quantitative PCR and SDS -polyacrylamide gel electrophoresis , respectively.t test was used for data analysis .Results The sensitivity of mutant Acinetobacter baumannii strains to meropenem and most antibiotics was reduced , except to imipenem, amikacin and polymyxin; and the reduced sensitivity to meropenem in MS2 and MS3 was of genetic stability.ERIC-PCR showed 100%homology between the mutant strains and parental strains .Both carbapenemase and metallo -β-lactamase were negative in mutant strains and parental strains , and only OXA-51 gene was found.The expressions of adeB gene in mutant strains were 24.26 ±0.91, while those in parental strains were 22.81 ±0.38, and the difference was not significant (t =2.534, P >0.05).Outer membrane protein with molecular weight 54 000 was missing in MS1, while that with molecular weight 47 000 was missing in MS2 and MS3.Conclusion Reduced antibiotics sensitivity in meropenem -induced Acinetobacter baumannii may be correlated with the deficiency of outer membrane protein with molecular weight 47 000.

Outer membrane proteins and lipopolysaccharides mediated antibody response against bovine Pasteurella multocida type B-2

Aims: The activation of cellular and humoral immunity depends upon nature of antigens. Complex proteins like bacterial outer membrane proteins (OMP) usually successfully activate both humoral and cellular immunity. Whereas antigens like bacterial lipopolysaccharides (LPS) usually elicit T-independent immunity i.e. humoral immunity without the activation of cellular immune wing. The present study was under taken to evaluate the comparative immunologic behavior of both the important molecules (bacterial lipopolysaccharide and outer membrane proteins) of Pasteurella multocida alone and in combination in bovine calves in field conditions. Methodology and results: Pasteurella multocida was isolated, purified and identified from an outbreak by mean of culture and biochemical methods. The pathogenicity of the confirmed isolates was done in rabbits (Oryctolagus cuniculus) on the principles of Koch’s postulates. Alum based vaccine against P. multocida was prepared and antibody titer against Outer membrane protein (OMP) and lipopolysaccharides (LPS) were determined by complement fixation test (CFT). The results showed that the antibody titer against OMP and LPS in whole culture vaccine is significantly higher than the respective tested vaccines. These results concluded that OMP no doubt is an active T-dependent immunogenic molecule but its immunogenicity increases many times when combined with LPS in whole culture vaccine. Conclusion, significance and impact of study: Lipopolysaccharides (LPS) in combination with outer membrane proteins (OMP) synergistically boost the humoral immune response in vaccinated animal.

Surface interactions between two of the main periodontal pathogens: Porphyromonas gingivalis and Tannerella forsythia

PURPOSE: Porphyromonas gingivalis and Tannerella forsythia have been implicated as the major etiologic agents of periodontal disease. These two bacteria are frequently isolated together from the periodontal lesion, and it has been suggested that their interaction may increase each one's virulence potential. The purpose of this study was to identify proteins on the surface of these organisms that are involved in interbacterial binding. METHODS: Biotin labeling of surface proteins of P. gingivalis and T. forsythia and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was performed to identify surface proteins involved in the coaggregating activity between P. gingivalis and T. forsythia. RESULTS: It was found that three major T. forsythia proteins sized 161, 100, and 62 kDa were involved in binding to P. gingivalis, and P. gingivalis proteins sized 35, 32, and 26 kDa were involved in binding to T. forsythia cells. CONCLUSIONS: LC-MS/MS analysis identified one T. forsythia surface protein (TonB-linked outer membrane protein) involved in interbacterial binding to P. gingivalis. However, the nature of other T. forsythia and P. gingivalis surface proteins identified by biotin labeling could not be determined. Further analysis of these proteins will help elucidate the molecular mechanisms that mediate coaggregation between P. gingivalis and T. forsythia.

Analysis of the expression of the outer membrane protein in carbapenem-resistant Acinetobacter baumannii / 国际检验医学杂志

Objective To Screen the carbapenem-resistant acinetobacter baumannii so as to understand the drug resistance,and to analyze the outer membrane protein expression between the carbapenem-resistant Acinetobacter baumannii and the sensitive strains.Methods The twofold agar dilution method was used to screen the carbapenem-resistant acinetobacter baumannii.PCR technique was used to detect the outer membrane protein-encoding gene carO.SDS-PAGE was used to analyze the expression of outer membrane protein.Results 32 strains were carbapenem-resistant acinetobacter baumannii separated from 1 10 strains,which were 100% sensitive to polymyxin B and were resistant to other drugs with different degrees O.They all carried carO gene.There were different protein bands between the carbapenem-resistant strains and the sensitive strains,in which two protein bands of 50× 10 3 and 22×10 3 were recognized as outer membrane proteins through the analysis of SDS-PAGE.Conclusion Drug resistance of acinetobacter baumannii is serious,and the outer membrane protein expression between the carbapenem-resistant strains and the sensitive strains presents discrepancy.

Immunoproteomic analysis of outer membrane proteins of Aeromonas hydrophila strain ATCC7966 / 中华微生物学和免疫学杂志

Objective To identify highly sensitive and specific antigens in Aeromonas hydrophila strain ATCC7966 by using immunoproteomics.Methods Outer membrane proteins were extracted from the Aeromonas hydrophila strain by using two-dimension electrophoresis and identified by LC-LTQ-XL-MS ( liq-uid chromatography coupled with linear ion trap mass spectrometry).Western blot assay was performed to screen out the immunogenic proteins.Results A total of 43 peptides representing 39 proteins were identi-fied by LC-LTQ-XL-MS.Among the 39 proteins, 69% were outer membrane proteins and 12% were inner membrane proteins.They were involved in the process of transportation, cell motility, biosynthesis, etc. One candidate vaccine antigen was identified by using two-dimensional Western blot analysis .Conclusion The immunoproteomics approach could be used to identify immunogenic proteins of Aeromonas hydrophila. This study provided references for further investigation on candidate vaccine antigens.

Lipopolysaccharide and outer membrane proteins of Leptospira interrogans induce macrophage apop-tosis via Fas/FasL pathway / 中华微生物学和免疫学杂志

Objective To investigate the role of pathogenic Leptospira interrogans lipopolysaccha-ride (L-LPS) and outer membrane proteins (L-OMP) in the apoptosis of mouse macrophages (J774A.1) and their association with Fas/FasL pathway .Methods Phenol-water extraction and Triton X-114 phase separation were used to extract L-LPS and L-OMP from L.interrogans serogroup icterohaemorrhagiae serovar Lai strain Lai, respectively.Polymyxin B ( PMB) and protease K ( PK) were used to treat L-LPS and L-OMP, respectively.J774A.1 cells were stimulated by L.interrogans strain Lai with or without ultraviolet inactivation.In parallel, the cells were stimulated by extracted L-LPS and L-OMP with or without PMB and PK treatments .The apoptosis and necrosis of J 774 A.1 cells before and after treatment were detected by flow cytometry.The siRNAs were used to silence the expression of Fas or FasL gene in J 774A.1 cells and their inhibitory effects were further validated by using real-time fluorescent quantitative RT-PCR.Flow cytometry was used to detect the effects of L-LPS or L-OMP on the apoptosis of J774A.1 cells with Fas or FasL gene-knockdown .Results L.interrogans strain Lai with or without ultraviolet inactivation could cause similar early apoptosis rates (47.1%and 55.6%) and late apoptosis/necrosis rates (7.6%and 7.9%).The ear-ly apoptosis rates of 1×105 J774A.1 cells were 40.4%and 34.0%after the treatment with 100 ng of L-LPS and 100 μg of L-OMP for 4 h.The late apoptosis/necrosis rates of the cells were 7.5%and 6.9%upon the treatments with L-LPS and L-OMP, respectively.However, the apoptosis or necrosis of the cells was not ob-served when using L-LPS and L-OMP pre-treated by PMB and PK, respectively.Silenced expression of Fas or FasL gene reduced the L-LPS-induced J774A.1 cells apoptosis (P<0.05), while decreased early apopto-sis rate of J774A.1 cells mediated by L-OMP was only observed in Fas gene-knockdown cells (P<0.05). Conclusion Both L-LPS and L-OMP can cause the Fas/FasL-associated apoptosis of macrophages , which is beneficial for L.interrogans to establish the productive infection in hosts .

Padronização e validação de elisa indireto para o diagnóstico da leptospirose bovina / Standardization and validation of elisa for diagnosis of bovine leptospirosis

A leptospirose é uma zoonose que causa sérios danos à saúde dos animais. Por se tratar de uma das doenças de maior impacto econômico, o correto diagnóstico e vigilância epidemiológica são fundamentais para o controle da infecção. Objetivou-se padronizar e validar o teste de ELISA indireto empregando proteínas de membrana externa (PME) do sorovar Hardjo como antígeno (ELISA-PME/Hardjo), tendo o teste de Soroaglutinação Microscópica (SAM) como referência. O ELISA-PME/Hardjo foi padronizado utilizando-se amostras de soro de 15 bovinos positivos e 15 negativos no exame de SAM. A PME/Hardjo foi avaliada nas concentrações de 0,35 µg/µL, 0,17 µg/µL, 0,08 µg/µL e 0,04 µg/µL. As amostras de soro foram testadas nas diluições 1:50, 1:100, 1:500 e 1:1000, e o conjugado anti IgG 1:5000 e 1:10000. A validação do teste foi feita utilizando-se 218 amostras de soro bovino. A padronização do ELISA-PME/Hardjo indicou que a melhor concentração protéica para sensibilização da placa foi de 0,08 µg/µL, diluição do anticorpo primário 1:50 e do conjugado anti-IgG 1:5000. Das 218 amostras submetidas ao teste de SAM, 86 (39%) foram positivas, e 132 (61%) negativas. Já o ELISA-PME/Hardjo identificou 121 (55%) amostras positivas e 97 (45%) negativas. A sensibilidade foi de 100% e especificidade 73%. A comparação dos testes de SAM e ELISA demonstrou concordância de 0,83% e índice Kappa de 0,68 (p<0,0001). O ELISA-PME/Hardjo mostrou ser um teste sensível, indicando seu uso potencial como exame de triagem no diagnóstico da leptospirose bovina.

Leptospirosis is a zoonotic disease that causes serious health risks to animals. It is a disease of high economic impact, therefore the correct diagnosis and surveillance are essential to control infection. The aim of this study was to standardize and validate an indirect ELISA using outer membrane proteins (OMPs) of serovar Hardjo as the antigen of the test (ELISA-OMP/Hardjo), using the microscopic agglutination test (MAT) as a reference. The ELISAOMP/Hardjo was standardized using 15 serum samples from positive animals and 15 negative in the MAT. The OMP / Hardjo was evaluated at concentrations of 0.35 µg / µL, 0.17 µg / µL, 0.08 µg / µL and 0.04 µg / µL. Serum samples were tested at dilutions 1:50, 1:100, 1:500, 1:1000, and anti IgG conjugate in 1:5000 and 1:10000. The validation of the test was performed using 218 serum samples. The standardization of ELISA-OMP/Hardjo indicated that the best protein concentration for sensitization of the plate was 0.08 µg / µL, 1:50 dilution of primary antibody and conjugated anti-IgG 1:5000. Of the 218 samples tested in MAT, 86 (39%) were positive and 132 (61%) negative. ELISA-OMP/Hardjo already identified 121 (55%) positive samples and 97 (45%) negative. The sensitivity was 100% and specificity 73%. Comparison of MAT and ELISA tests showed concordance of 0.83% and Kappa of 0.68 (p <0.0001). The ELISA-OMP/Hardjo proved to be a sensitive test, indicating its potential as a screening tool in the diagnosis of bovine leptospirosis.

The detection of the binding protein of chlamydiaphage phiCPG1 capsid protein Vp1 on chlamydial outer membrane of serotype D / 中华传染病杂志

Objective To investigate the binding protein of chlamydiaphage phiCPG1 capsid protein Vp1 on chlamydia trachomatis outer membrane.Methods The bacterium with recombinant plasmid Vp1/pet30a( + ) was induced.The expressed protein was purified by gel recycling.FarWestern blot was utilized to' investigate the binding protein of Vp1 on chlamydial outer membrane,including recombinant polymorphic outer membrane protein (rPmp) and major outer membrane protein (MOMP).Results The recombinant protein Vp1 was successfully expressed in E.coli.Monoclonal antibody against Vp1 was used as primary antibody in Western blot,and no specific band was present,which indicated that the monoclonal antibody did not specifically bind with any rPmp.Far-Western blot results showed that there was an obvious band for the rPmpI,but no specific band for other rPmp and MOMP,which suggested that Vp1 could specifically bind with rPmpI protein on the chlamydial outer membrane of serotype D.Conclusions There is a binding site of Vp1 on the chlamydia trachomatis outer membrane.Vp1 may play an important role in the interaction between the chlamydiaphage and the chlamydiae.

Diversity of outer membrane protein expression of Leptospira interrogans during infection of human THP-1 monocytes / 中华微生物学和免疫学杂志

ObjectiveTo determine the diversity of outer membrane protein expression of Leptospira interrogans during infection of human THP-1 monocytes,and protein antigen candidates for developing leptospiral genetically engineering vaccines.MethodsThe outer membrane proteins(OMPs) of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai before or after infection of human THP-1 monocyte line were extracted using Triton X-114 method.The OMPs extracts were separated by two-dimensional gel electrophoresis(2-DGE) and then detected using silver staining method.Four up-regulated and four down-regulated OMPs were selected for hydrolysis by trypsin and then identified by using liquid chromatography-tandem mass(LC-MS/MS) method.The transmembrane regions and signal peptides in the eight target OMPs were analyzed using bioinformatic software.Several real-time fluorescent quantitative RT-PCRs were performed to determine the mRNA level changes of the eight target genes of L.interrogans strain Lai before or after infection of THP-1 cells.The prokaryotic expression systems of target genes were generated and the immunoprutection of target recombinant proteins was determined using leptospire-infected guinea pigs model.ResultsAfter a 60 min infection of THP-1 cells,four OMPs( Loa22,GroEL,F0F1 ATP synthase alpha- and beta-subunits) of L interrogans strain Lai were noticeably up-regulated ( P＜0.05 ),while the other four OMPs( FlaB2,LigB,OmpA family protein and OmpA) were significantly down-regulated (P＜0.05).The results of real-time fluorescent quantitative RT-PCRs were coincident with those confirmed by the 2-DGE phus silver staining.The bioinformatic analysis indicated that among the eight OMPs,OmpA and OmpA family protein belonged transmembrane proteins,while the rest had no membrane structure.Loa22,LigB and OmpA family protein contained a signal peptide in their sequences.200 μg of the recombinant proteins rLoa22 and rGroEL presented 75.0％ immunoprotective rates in the infected guinea pigs.Conclusion An obvious change of the OMP expression map of L.interrogans strain Lai occurs during infection of host cells.The up-regulated leptospiral OM Ps during infection,especially for the GroEL and Loa22 proteins,can be used as the immunogen candidates for developing leptospiral genetically engineering vaccines.

Immune responses induced by the recombinant major outer membrane protein vaccine against Chlamydia trachomatis E serotype in rhesus monkeys / 中华皮肤科杂志

[Objective] To observe the specific immune responses induced by the recombinant major outer membrane protein (rMOMP) vaccine against Chlamydia trachomatis E serotype in rhesus monkeys.[Methods] Six rhesus monkeys were equally divided into three groups:adjuvant and protein group vaccinated with purified rMOMP and Freund's adjuvants,adjuvant group immunized with Freund's adjuvants only,and control group immunized with phosphate buffer.All the rhesus monkeys were intramuscularly immunized in the triceps brachii for 3 times at a 2-week interval.Two weeks after the last vaccination,serum,vaginal wash and venous blood samples were collected from the rhesus monkeys,and lymphocytes were isolated from the blood samples.Enzyme linked immunosorbent assay (ELISA) was performed to determine the specific IgG antibody and interferon level in sera and secretory IgA (sIgA) level in wash samples,and methyl thiazolyl tetrazolium (MTT) assay to evaluate the proliferation of lymphocytes after stimulation with Chlaraydia trachomatis serotype E elementary bodies.Delayed hypersensitivity was observed in rhesus monkeys challenged by inactivated Chlamydia trachomatis serotype E elementary bodies.In vitro antibody neutralization assay was conducted with the serum from rhesus monkeys.Indirect immunofluorescenee was used to detect Chlamydia trachomatis in exfoliative vaginal cells from rhesus monkeys from week 1 to 10 after challenge with Chlamydia trachomatis.Data were statistically analyzed by using one-way analysis of variance and least significant difference (LSD) test with the SPSS 14.0 software.[Results] The adjuvant and protein group differed statistically from the adjuvant group and control group in the serum level of specific IgG antibody (1.718 ± 0.213 vs.0.841 ± 0.315 and 0.791 ±0.437,both P＜ 0.05),interferon ((1086 ± 121.730) ng/L vs.(409 + 53.440) ng/L and (162 ± 48.046) ng/L,both P＜ 0.05),lymphocyte proliferation index (7.012 ± 1.026 vs.4.473 ± 1.850 and 1A26 ± 1.104,both P＜0.01 ) and the diameter of nodus in delayed hypersensitivity assay ( ( 1 1 ± 2.134) mm vs.(3 ± 0.914) mm and 0,both P ＜ 0.01 ).After attack,the exfoliative cells kept positive for Chlamydia trachomatis in the adjuvant and protein group from week 1 to 5,and in the other 2 groups from week 1 to 10,but were negative in the adjuvant and protein group from week 6 to 10.[Conclusion] The rMOMP vaccine can induce a specific,protective,humoral and cellular immune response against Chlamydia tracbomatis in rhesus monkeys.